CN112018766B - High-voltage power distribution cabinet - Google Patents
High-voltage power distribution cabinet Download PDFInfo
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- CN112018766B CN112018766B CN202010996703.XA CN202010996703A CN112018766B CN 112018766 B CN112018766 B CN 112018766B CN 202010996703 A CN202010996703 A CN 202010996703A CN 112018766 B CN112018766 B CN 112018766B
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
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Abstract
The invention discloses a high-voltage power distribution cabinet, which comprises: the first power supply branch is electrically connected with a power supply end incoming terminal, an isolating switch module, a breaker module and a first outgoing terminal in sequence; the first outlet terminal is connected with a first transformer; the second power supply branch is electrically connected with the power supply end incoming terminal, the isolating switch module and the primary coil of the second transformer in sequence; the first secondary coil of the second transformer is connected with an auxiliary power supply outlet terminal, and the second secondary coil of the second transformer is connected with the detection module; wherein the detection module is configured for detecting an actual current and/or an actual voltage. The high-voltage power distribution cabinet provided by the invention can provide power for the power utilization functional device in the high-voltage power distribution cabinet on the occasion that no additional auxiliary control power supply is arranged and the rear stage is connected with the large-capacity main transformer, is flexible to use and is particularly suitable for being matched with different outdoor power distribution systems.
Description
Technical Field
The invention belongs to the technical field of electrical equipment, and particularly relates to a high-voltage power distribution cabinet.
Background
The high-voltage power distribution cabinet is indispensable electrical equipment in a power distribution system and directly influences the normal operation and the power supply service quality of the power distribution system. The high-voltage power distribution cabinet is mainly used for opening and closing, controlling and protecting electric equipment in the process of power generation, power transmission, power distribution and electric energy conversion of a power system. The traditional high-voltage power distribution cabinet mainly comprises a cabinet body and a circuit breaker, wherein the interior of the cabinet body is divided into a main bus chamber, a circuit breaker chamber, a cable chamber, a relay, an instrument chamber, a secondary terminal chamber and the like, so that the circuit breaker, a disconnecting switch, a load switch, an operating mechanism and various protection devices can be conveniently and specially configured.
Conventional power distribution systems integrated with high-voltage power distribution cabinets are mainly used in power distribution rooms. The distribution room can provide power of various parameters required by the distribution system to meet the use requirements of different devices. However, with the continuous development of electrical equipment, many high voltage power distribution cabinets need to be used outdoors, such as outdoor charging stations. There is no additional auxiliary control power supply in outdoor environment, and its back stage may need to be connected with large-capacity transformer, and it also needs to meet the completely different size and material standard from indoor. Therefore, the traditional high-voltage distribution cabinet only consisting of the cabinet body and the circuit breaker cannot meet the outdoor use requirement.
The above information disclosed in this background section is only for enhancement of understanding of the background section of the application and therefore it may contain prior art that does not constitute known technology to those of ordinary skill in the art.
Disclosure of Invention
The invention designs and provides a high-voltage power distribution cabinet aiming at the problem that the high-voltage power distribution cabinet only consisting of a cabinet body and a circuit breaker in the prior art can not meet the outdoor use requirement of a power distribution system, and particularly the problem that no additional auxiliary control power supply is arranged outdoors and a high-capacity transformer needs to be connected at the rear stage.
In order to realize the purpose of the invention, the invention is realized by adopting the following technical scheme:
a high voltage distribution cabinet comprising: the first power supply branch is electrically connected with a power supply end incoming terminal, an isolating switch module, a breaker module and a first outgoing terminal in sequence; the first outlet terminal is connected with a first transformer; the second power supply branch is electrically connected with the power supply end incoming terminal, the isolating switch module and the primary coil of the second transformer in sequence; the first secondary coil of the second transformer is connected with an auxiliary power supply outlet terminal, and the second secondary coil of the second transformer is connected with the detection module; wherein the detection module is configured for detecting an actual current and/or an actual voltage.
Further, the detection module comprises: the voltage detection end is connected with the second secondary coil of the second transformer; the first current detection end is connected with a first current transformer, and the first current transformer is arranged between the circuit breaker module and the first wire outlet terminal.
Further, the detection module further includes: and the second current detection end is connected with a second current transformer, the second current transformer is arranged between the circuit breaker module and the first wire outlet terminal, and the measurement precision of the second current transformer is higher than that of the first current transformer.
Still further, the circuit breaker module includes: the first switching element is provided with a plurality of first controllable contacts which are respectively connected in series in a plurality of phase lines of the first power supply branch circuit; the multiple second controllable contacts of the second switching element are respectively connected with the multiple first controllable contacts of the first switching element in parallel; and a plurality of power resistors, one of the power resistors being connected in series with each of the second controllable contacts.
Preferably, the first switching element is a vacuum circuit breaker, and the second switching element is a vacuum contactor.
Further, the method also comprises the following steps: and the overvoltage protection module is connected with the first power supply branch circuit.
Further, the method also comprises the following steps: the high-voltage live display module is connected with the first power supply branch circuit and is arranged at the front end of the isolating switch module.
Further, the method also comprises the following steps: the fuse, the fuse sets up in the second power supply branch road, the one end of fuse is connected the isolator module, the other end of fuse is connected the primary coil of second transformer.
Preferably, the auxiliary power supply outlet terminal outputs 380V voltage, and the auxiliary power supply outlet terminal adopts a three-phase four-wire system.
Preferably, the high-voltage power distribution cabinet is a 10kV high-voltage power distribution cabinet.
Compared with the prior art, the invention has the advantages and positive effects that:
the high-voltage power distribution cabinet can provide power for the electricity utilization functional device in the high-voltage power distribution cabinet on the occasion that no additional auxiliary control power supply exists and a large-capacity main transformer is connected in the rear stage, is flexible to use, is particularly suitable for being matched with different outdoor power distribution systems, forms an actual voltage detection point under the condition that no additional hardware equipment is arranged, improves the safety of the power distribution systems, and releases more space in the cabinet.
Other features and advantages of the present invention will become more apparent from the following detailed description of the invention when taken in conjunction with the accompanying drawings.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
Fig. 1 is a schematic block diagram of a first embodiment of a high voltage distribution cabinet according to the present disclosure;
fig. 2 is a schematic block diagram of a second embodiment of the high voltage distribution cabinet disclosed in the present invention;
fig. 3 is a circuit diagram of the high voltage distribution cabinet shown in fig. 2;
fig. 4 is a circuit diagram of a detection module in the high voltage distribution cabinet shown in fig. 2.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings and examples.
It should be noted that in the description of the present invention, the terms of direction or positional relationship indicated by the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, which are merely for convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
Aiming at the problem that a high-voltage power distribution cabinet only consisting of a cabinet body and a circuit breaker in the prior art can not meet the outdoor use requirement of a power distribution system, particularly the problem that no additional auxiliary control power supply exists outdoors and the rear stage needs to be connected with a large-capacity transformer, the high-voltage power distribution cabinet with a brand-new design is shown in figure 1. The high voltage distribution cabinet 1 is preferably a 10kV high voltage distribution cabinet. In particular, a first power supply branch (indicated by a solid arrow in fig. 1 and 2) and a second power supply branch (indicated by a dashed arrow in fig. 1 and 2) are designed in the high voltage distribution cabinet 1. The first power supply branch is electrically connected with a power supply end incoming terminal 11, a disconnecting switch module 12, a breaker module 13 and a first outgoing terminal 14 in sequence; wherein the first outlet terminal 14 is connected to a first transformer 15. The first power supply branch circuit is configured as a main bus of the power distribution cabinet, the specification standard of the main bus and the rated current required to be achieved are calculated according to actual needs, and the first transformer 15 is a large-capacity main transformer. The disconnector module 12 and the circuit breaker module 13 are mutually matched and jointly configured to perform the following functions, one of which is to connect or disconnect the load current of the high-voltage line in a state that the power distribution system is operating well; and secondly, accident hidden danger occurs in a power distribution system, fault current is cut off in the shortest time, and the influence range of the fault problem is controlled. Maintaining proper operation and operation of the power distribution system.
The second power supply branch is designed to be electrically connected with a power supply end incoming terminal 11, an isolating switch module 12 and a primary coil 17 of a second transformer 16 in sequence; the first secondary winding 18 of the second transformer 16 is connected to an auxiliary power outlet terminal 20, and the auxiliary power outlet terminal 20 is further connected to and provides 220V or 380V power to functional modules in the high voltage distribution cabinet 1, such as a switching power supply, an air conditioner, a lighting device, a pre-charging module, and the like. The second secondary winding 19 of the second transformer 16 is connected to a detection module 21, the detection module 21 being configured for detecting the actual current and/or the actual voltage. And the second power supply branch circuit is configured to be a branch bus of the power distribution cabinet. The second transformer 16 arranged in the second power supply branch is configured to perform the function of supplying power to the power consuming functional devices in the high voltage distribution cabinet 1 in the absence of an additional auxiliary control power supply and in the case of a subsequent connection to a large capacity main transformer, and the function of forming a detection point of the main bus voltage without the provision of hardware equipment. For example, if the primary input of the power source terminal 11 is 10000V and the output of the second secondary winding 19 of the second transformer 16 is 100V, the transformer transformation ratio of the second transformer 16 is 10000: 100 = 100: 1. The detection module 21 only needs to sample the voltage u of the secondary winding 19 of the auxiliary transformer, so as to obtain the actual voltage of the main bus as 100u. The detection module 21 may be a separate processor chip, or may be a processor chip integrated in the integrated protector, and the model thereof is not further limited herein. In a conventional power distribution cabinet, a voltage transformer is generally adopted to detect voltage. In the actual working operation of the voltage transformer, the primary winding enters a high-voltage state, and the secondary winding is at a low voltage. However, the voltage transformer may have a problem that the insulation performance between the two windings is lost, and at this time, the secondary winding automatically obtains high voltage, so that both the equipment and the operator face safety risks. In the high-voltage power distribution cabinet 1 provided by the invention, the sampling, detection and monitoring of the actual voltage are realized under the condition of not arranging a voltage transformer, the safety of a power distribution system is improved, and more space in the cabinet is released.
The detection module 21 is also configured for detecting the actual current of the main bus. Specifically, as shown in fig. 2, the detection module 21 includes a voltage detection terminal U. Wherein the voltage detection terminal U is connected to the second secondary winding 19 of the second transformer 16. The detection module 21 is further designed with a first current detection terminal I1, the first current detection terminal I1 is connected to a first current transformer 22, and the first current transformer 22 is disposed between the circuit breaker module 13 and the first wire outlet terminal 14. For example, the rated current of the primary winding of the first current transformer 22 is 1250A, and the rated current of the secondary winding of the first current transformer 22 is 5A, that is, the transformation ratio of the first current transformer 22 is 1250A/5a =250, when the first current detection end I1 of the detection module 21 receives a detection value I of the first current transformer 22, the actual current of the main bus is 250I, so that the sampling of the voltage and the current is realized at the same time.
As shown in fig. 2, in the high voltage distribution cabinet 1 provided in this embodiment, a different protection mechanism is provided through a redundant design of current sampling. Specifically, the detection module 21 further includes a second current detection terminal I2, and the second current detection terminal I2 is connected to the second current transformer 23. A second current transformer 23 is disposed between circuit breaker module 13 and first outlet terminal 14. The measurement accuracy of the second current transformer 23 is higher than that of the first current transformer 22. In a common operation process, the power distribution cabinet outputs and displays an actual current value based on an input value of the first current detection terminal I1 of the detection module 21, and executes an action of cutting off a fault current based on an input value of the second current detection terminal I2 of the detection module 21.
From the circuit connection, the whole high-voltage power distribution cabinet 1 preferably adopts a three-phase four-wire system, the auxiliary power supply outlet terminal 20 outputs 380V voltage, and the three-phase four-wire system adopted by the auxiliary power supply outlet terminal 20 is 220V voltage between any two live wires. When the first secondary winding 18 of the second transformer 16 is connected to the auxiliary power outlet terminal 20, 220V and 380V power can be simultaneously provided. As shown in fig. 3, a power supply terminal R, S, T provides three-phase 10kV alternating current, and correspondingly, a first power supply branch is provided with a disconnecting switch QS1, a circuit breaker module, a first current transformer 1TA and a second current transformer 2TA. The second power supply branch is electrically connected with a power supply end inlet terminal R, S, T, an isolating switch QS1 and a primary coil A, B, C of a second transformer in sequence, first secondary coils a1, b1 and c1 of the second transformer are connected with an auxiliary power supply outlet terminal and further connected to the functional module 26, and second secondary coils a2, b2 and c2 of the second transformer are connected with the detection module. As shown in fig. 4, the outlet terminals a600, B600, C600 and the zero line N600 of the second secondary coils a2, B2 and C2 are respectively connected to the pins C1, C2, C3, D1, D2 and D3 of the detection module, the first current transformer 1TA is connected to the first current detection terminal of the detection module, that is, the pins C7, C8, D7 and D8 of the detection module are respectively connected to the pins 1TAa, 1TAb and 1TAc, and the second current transformer 2TA is connected to the second current detection terminal of the detection module, that is, the pins C9, C10, C11, D9, D10 and D11 of the detection module are respectively connected to the pins 2TAa, 2TAb and 2 TAc.
As shown in fig. 3, based on a three-phase four-wire connection design, the circuit breaker module 13 includes a first switching element MCB1, wherein multiple first controllable contacts of the first switching element MCB1 are respectively connected in series in multiple phase lines of the first power supply branch. The first switching element MCB1 is preferably a vacuum circuit breaker, which uses a spring-like contact, the spring having a certain elastic flexibility to ensure tripping within 40 milliseconds after the occurrence of a fault current.
Since the capacity of the first transformer 15 of the later stage can reach 9000KVA, when the first transformer 15 is charged, the magnetizing inrush current is often one of factors causing the first transformer 15 to trip by mistake so that the charging is unsuccessful. The magnetizing inrush current means that when the no-load transformer is just connected with a power supply, a large current appears on the power supply side, and the value of the large current can be 6-8 times of the rated current. The reason for the magnetizing inrush current is the nonlinearity of the transformer core magnetization curve. The waveform of the inrush current and the amplitude thereof are not only related to the magnetization curve, but also related to the residual magnetism system of the iron core and the phase position when the voltage is put into use. The existence of the residual magnetism increases the saturation magnetic flux in the iron core, and further increases the excitation current. When the voltage input phase is 0 °, the inrush current is maximum. The actual inrush current is a transient current that is continuous in time. The amplitude of the waveform will gradually decrease over time due to the resistance of the windings. The inrush current waveform is deviated to one side of a time axis at the beginning, then the inrush current waveform gradually enters a steady state, namely the current is gradually symmetrical to a time value, finally the current is changed into a normal excitation current with small amplitude and completely symmetrical to the time value, and the normal excitation current is 90 degrees out of phase with a voltage. In a three-phase transformer, inrush currents may occur in each phase. The inrush current is a non-sinusoidal waveform and contains many harmonic components, of which the proportion of the direct current and third harmonic components is large, and the influence of these harmonics needs to be suppressed. To solve this problem, as shown in fig. 3, a second switching element KM1 is also specifically designed in the breaker module 13. The second controllable contacts of the second switching element KM1 are connected in parallel with the first controllable contacts of the first switching element MCB1, respectively. Each of the second controllable contacts is connected in series with a power resistor (shown as R7, R8 and R9 in fig. 3). When the first supply branch has just been connected, it may be preferable to keep the multiple first controllable contacts of the first switching element MCB1 open and the multiple second controllable contacts of the second switching element KM1 conductive. This limits the primary side inrush current of the first transformer 15 to a relatively small value, and the power of the power resistors is sufficient to limit the amount of heat generated by the primary side inrush current. When the primary side magnetic field of the first transformer 15 is completely established, the multiple first controllable contacts of the first switching element MCB1 are switched on, the multiple second controllable contacts of the second switching element KM1 are switched off, the main bus and the first transformer 15 are switched on, and the first transformer 15 is put into operation, so that the problem of front-stage power supply impact caused by an excessively large primary side inrush current value is avoided. The second switching element is preferably a vacuum contactor.
In particular, an overvoltage protection module 25 (labeled F01 in the specific circuit diagram of fig. 3) and a high-voltage live display module 24 (labeled a01 in the specific circuit diagram of fig. 3) are also provided in the high-voltage power distribution cabinet 1. The overvoltage protection module 25 is connected to the first power supply branch, and the high-voltage live display module 24 is also connected to the first power supply branch. The high-voltage live display module 24 is arranged at the front end of the isolating switch module 12. A fuse (shown as Fu1, fu2, and Fu3 in fig. 3) is further disposed in the second power supply branch, one end of the fuse is connected to the isolation switch module 12, and the other end of the fuse is connected to the primary coil 17 of the second transformer 16. The overvoltage protection module 25, the high-voltage live display module 24 and the fuse play a protection role respectively.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof; such modifications and substitutions do not depart from the spirit and scope of the corresponding claims.
Claims (7)
1. A high voltage distribution cabinet, characterized in that includes:
the first power supply branch is electrically connected with a power supply end incoming terminal, an isolating switch module, a breaker module and a first outgoing terminal in sequence; the first outlet terminal is connected with a first transformer; and
the second power supply branch is electrically connected with a power supply end incoming terminal, the isolating switch module and a primary coil of a second transformer in sequence; the first secondary coil of the second transformer is connected with an auxiliary power supply outlet terminal, and the second secondary coil of the second transformer is connected with the detection module; the second transformer is configured to provide power for the power utilization functional device in the high-voltage power distribution cabinet; the detection module is configured for detecting an actual current and/or an actual voltage; the detection module comprises: the voltage detection end is connected with the second secondary coil of the second transformer; the first current detection end is connected with a first current transformer, and the first current transformer is arranged between the circuit breaker module and a first wire outlet terminal; the second current detection end is connected with a second current transformer, the second current transformer is arranged between the circuit breaker module and the first wire outlet terminal, and the measurement precision of the second current transformer is higher than that of the first current transformer; the auxiliary power supply outlet terminal outputs 380V voltage, and the auxiliary power supply outlet terminal adopts a three-phase four-wire system.
2. High voltage distribution cabinet according to claim 1,
the circuit breaker module includes:
the first switching element is provided with a plurality of first controllable contacts which are respectively connected in series in a plurality of phase lines of the first power supply branch circuit;
the multiple second controllable contacts of the second switching element are respectively connected with the multiple first controllable contacts of the first switching element in parallel; and
a plurality of power resistors, one of the power resistors being connected in series with each of the second controllable contacts.
3. High voltage distribution cabinet according to claim 2,
the first switching element is a vacuum circuit breaker, and the second switching element is a vacuum contactor.
4. High voltage distribution cabinet according to claim 2,
further comprising:
and the overvoltage protection module is connected with the first power supply branch circuit.
5. High voltage distribution cabinet according to claim 2,
further comprising:
the high-voltage live display module is connected with the first power supply branch and arranged at the front end of the isolating switch module.
6. High voltage distribution cabinet according to claim 2,
further comprising:
the fuse, the fuse sets up in the second power supply branch road, the one end of fuse is connected the isolator module, the other end of fuse is connected the primary coil of second transformer.
7. High voltage distribution cabinet according to claim 1,
the high-voltage power distribution cabinet is a 10kV high-voltage power distribution cabinet.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010996703.XA CN112018766B (en) | 2020-09-21 | 2020-09-21 | High-voltage power distribution cabinet |
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| CN202010996703.XA CN112018766B (en) | 2020-09-21 | 2020-09-21 | High-voltage power distribution cabinet |
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| CN112018766A CN112018766A (en) | 2020-12-01 |
| CN112018766B true CN112018766B (en) | 2022-10-28 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN202103403U (en) * | 2011-07-04 | 2012-01-04 | 山西兰花科技创业股份有限公司 | 630A mining flame-proof vacuum intelligent sub-feed switch |
| CN103812022B (en) * | 2013-12-31 | 2016-08-17 | 江苏天翔节能科技有限公司 | A kind of power distribution cabinet |
| CN105576608B (en) * | 2014-10-16 | 2018-04-06 | 上海船厂船舶有限公司 | Middle pressure transformer protection system |
| CN205212296U (en) * | 2015-11-19 | 2016-05-04 | 天津鼎一电气成套设备有限公司 | Box -type substation with remote alarm function |
| CN105425005B (en) * | 2015-12-09 | 2018-03-30 | 马鞍山钢铁股份有限公司 | The replacement device and method of factory's high-tension electricity electromagnetic type voltage transformer |
| US20170214225A1 (en) * | 2016-01-22 | 2017-07-27 | Locus Energy, Inc. | Interconnect and metering for renewables, storage and additional loads with electronically controlled disconnect capability for increased functionality |
| CN206742857U (en) * | 2017-05-12 | 2017-12-12 | 厦门集控电气系统有限公司 | A kind of low-voltage distribution room outgoing line cabinet |
| CN109428330A (en) * | 2017-08-24 | 2019-03-05 | 株洲变流技术国家工程研究中心有限公司 | Electric railway auxiliary power supply system and control method with power circulation function |
| CN207977742U (en) * | 2018-01-26 | 2018-10-16 | 江苏省镇江船厂（集团）有限公司 | Boat-carrying high voltage shore power power receiving device |
| CN208461466U (en) * | 2018-06-25 | 2019-02-01 | 中铁第四勘察设计院集团有限公司 | Urban Railway Substation power supply system |
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